Why Is My New Water Heater Leaking?
A new water heater that leaks in its first year or two is usually leaking at a fitting that wasn't sealed or tightened, a drain valve that isn't fully closed, or a relief valve opening because of thermal expansion. Gas units can also drip condensation on the first heat-up. A true tank defect is rare, but it happens.
Finding water under a heater you just paid for is frustrating. The upside is that on a new install, the causes are short and easy to check. Most come down to how the heater was connected, or how the house plumbing reacts to it, rather than the heater itself.
Before anyone touches it, take photos. If the cause turns out to be workmanship or a factory defect, those first pictures matter.
Leaks in the First Few Days
Is it normal for a new gas water heater to drip at first?
It can be. When a gas heater fires on a tank full of cold water, water vapor from the flame condenses on the cold flue and drips onto the burner. You may hear sizzling and see a little water in the pan. It should stop within a few hours as the tank heats up. If it doesn't, it's not condensation. Our condensation vs. leak guide explains the difference in detail.
Loose or unsealed connections
The cold inlet, hot outlet, relief valve and gas line all get connected on install day. A threaded joint with too little tape or pipe dope, a flex connector washer that's pinched or missing, or a nut left hand-tight can all start dripping once the heater warms up and the metal expands. These leaks usually show up within hours or days.
The drain valve isn't fully closed
The drain valve near the bottom is opened during some installs to test or flush. If it's left a hair open, or its cap is missing, it drips. Factory plastic drain valves can also crack if they're bumped or overtightened. Check the spout with a dry paper towel. For more, see our page on a drain valve leaking.
Relief Valve Dripping on a New Heater
This is one of the most common calls about new heaters, and it's often not the heater's fault. The T&P relief valve opens when pressure or temperature gets too high. On a new tank, the valve is new too, so a drip from its pipe usually means pressure is the problem.
Why did the relief valve start leaking after my heater was replaced?
When water heats, it expands. If your home has a pressure-reducing valve on the main or a check valve at the meter, that extra water can't flow back to the street. Pressure climbs every time the heater runs, and the relief valve lets some water out. Sometimes a new PRV or meter check valve went in around the same time as the heater, and that's what changed. If there's no working expansion tank, adding one usually fixes it. See our expansion tank installation page.
What if the relief valve drips all the time?
A constant drip from a new valve is less common. It can be grit from the new install caught in the seat, very high water pressure, or a faulty valve. Check your pressure with a hose bib gauge. More on how these valves behave is on our relief valve leaking page.
Safety: Never cap or plug the relief valve pipe to stop a drip on a new heater. The valve is doing its job. Fix the pressure instead.
Could It Be a Defective Tank?
It's possible. Tanks are pressure-tested at the factory, but a weld can still fail, a tank can be damaged in shipping, or the lining can have a flaw. A tank defect usually shows as water seeping from the bottom seam, from under the jacket, or wet insulation behind the access panel, with all fittings and valves above it dry.
Can hard water ruin a new water heater this fast?
Not in a year or two. Apache Junction water runs about 13–16 grains per gallon of hardness, and that does shorten tank life here. Many local tanks show trouble at 7–9 years instead of the national 8–12. But hard water wears a tank over years. A leak in the first year or two points to an install issue, a pressure issue or a defect.
How do I tell a tank leak from a fitting leak?
Dry everything, then wrap each fitting, the relief valve threads and the drain valve with paper towels. Water from the tank body with dry towels above it is a tank leak. Our page on a water heater tank leaking covers what that means.
Warranty: Who to Call and What to Save
A new heater often has two kinds of coverage. The manufacturer's warranty covers the tank and parts, and the installer may stand behind the work they did. They're separate, and the terms vary a lot. Read your paperwork rather than assuming either one applies.
Call the installer first
If the leak is at a connection, valve or the drain, that's usually an installation question. Give them a chance to come back and look before you pay someone else.
Check the manufacturer's warranty
If the tank itself is leaking, look up the manufacturer's warranty using the model and serial number on the label. Some require registration or proof of purchase. Many cover parts but not labor.
What should I document for a warranty claim?
- Clear photos and a short video of where the water is coming from, before anything is changed
- The rating label: brand, model number and serial number
- Your receipt or invoice with the install date
- Any registration confirmation from the manufacturer
- Dated notes: when you first saw water, how much, and what you did
- Written findings from whoever inspects it
Tip: Don't throw away a leaking tank or failed part until the manufacturer or installer tells you what they need. Some warranty claims ask for the part or tank to be returned or inspected.
If water damaged floors or walls, your homeowners policy may be a separate question. Our page on whether insurance covers a water heater leak explains what's usually covered and what to photograph.
What to Do Right Now
- Slow the water. Close the cold shutoff above the heater and turn off the breaker or set the gas to "Pilot."
- Photograph everything. Wide shots and close-ups of the wet spots, the label and the floor.
- Find the source. Use the paper towel check on every joint from the top down.
- Call the installer if it's a connection or valve. Check the manufacturer's warranty if it's the tank.
- Get a second opinion if needed. If the installer isn't reachable or you're not sure, we can find the source and give you written findings.
A leak on a new heater is almost always fixable without another new heater. Apache Junction Water Heater Pros is open 24/7. Read more about our water heater leak repair in Apache Junction, or see every leak spot on our leak finder page.
New Water Heater Leaking: FAQs
How long should a new water heater be dry after installation?
It should stay dry from the start. A little condensation on a gas unit during the first heat-up can drip for a few hours. After that, any water on the tank, fittings or floor is a leak to track down, even if it's small.
Is a leaking new water heater covered by the warranty?
It depends on the cause and the terms. Tank defects are often covered by the manufacturer, but labor may not be. Leaks at fittings are usually an installation question. Check the manufacturer's warranty with your serial number and contact your installer.
Why did my relief valve start dripping after a new water meter or PRV?
A new check valve at the meter or a new pressure-reducing valve can make your plumbing a closed system. Water that expands while heating has nowhere to go, so pressure rises until the relief valve opens. An expansion tank on the cold line usually solves it.
Should I let the installer fix it or call someone else?
For connection and valve leaks, let the installer look first if they're reachable, since it may be covered by their work. If they can't come, or you have doubts about the diagnosis, a second opinion with written findings helps either way.
Can a new water heater leak because of high water pressure?
Yes. Pressure above about 80 psi strains every joint and can push the relief valve open. A hose bib gauge shows you the reading. If it's high, the pressure-reducing valve may need adjusting, replacing or adding.
Can I keep using a new water heater that's dripping?
For a small fitting drip, you can usually use it for a day with a towel or bucket in place while you arrange a fix. If water comes from the tank body, the bottom seam or behind the access panel, shut off the water and the power or gas until it's inspected.